Regarding the authenticity of the Hadeeth:
"[...] You [should] listen to & obey the ruler, and even if he strikes your back & takes your wealth,you listen & obey" (Muslim, 3/1476)
Part I) Status of the narration in Muslim
Part II) Other relevant chains & their status
Imam Muslim narrates from Muhammad ibn Sahl At-Tamimi & Abdullah ibn Abd-Ar-Rahman Ad.Darimi
-> Yahya ibn Hassaan -> Mu'awiyyah ibn Salaam -> Zayd ibn Salaam -> Abu Salaam Al-Habshi
-> Hudhayfa bin Al-Yamaan RA
-> Prophet - peace be upon him
The Hadeeth or rather specifically the addition in question ("...obey the ruler,and even if...") is Mursal & thus rejected
Other chains of this narration go back to Ahadeeth narrated by Imam Ahmad in his Musnad (#23318, 23321, 23496 & further branches)
They (at least) include Sakhr ibn Badr Al-'Ilji, who is not known to have narrated anything else except this from Subay' ibn Khalid...
Two further chains include 'Ali ibn Zayd or Nasr ibn 'Aasim narrating from Subay' ibn Khalid Al-Basri...
Also, there is no strong commendation for Subay' Al-Basri either.
Sh Al-Muqbil ibn Hadee Al-WadI'ee also declared this addition as rejected and thus the Hadeeth as weak =)